Impact thermoplastics: Combined role of rubbery phase volume and particle size on toughening efficiency

摘要: A relationship has been found for OSA (olefin-acrylonitrile-styrene) polymers between normalized Izod impact strength (ΔI/N) or yield stress (Δσy/N) with mean particle radius. These functions (which analytically include radius and rubbery phase volume) are representative of the toughening effect a single respect to styrene-acrylonitrile (SAN) rigid matrix. ΔI/N Δσy/N increase exponentially as function This approach, Izod, was also applied HIPS toughened nylon reported in literature similar results were obtained. In case nylon, however, values split two different curves related tough-brittle transition described that literature. Referring OSA, three samples (with largest radii more than 0.22 μm) fail brittle manner do not fit curve ΔI/N: they fit, Δσy/N. Further work must be done order investigate decisive role either interfacial adhesion (eventual lack these materials) mentioned before shear-yielding deforming materials. fact, behavior intermediate which deforms by crazing.